1. Field of the Invention
The present invention relates to an apparatus and method for binding individual pages for subsequent assembly in an album, such as a looseleaf photograph album.
2. Description of the Prior Art
The present invention is particularly concerned with the forming of album pages comprising a sheet of paperboard for retaining photographs or cards. The album page may include a plurality of pockets formed by sheets of clear plastic secured along their sides and bottom edges to the surface of the base sheet. An example of such an album page is shown in U.S. Pat. No. 3,735,516 to Winstrom, which is assigned to the assignee of the present invention. This patent also shows such an album page having the reinforcing tapes overlapping and bonded to the side edges of the sheet, with one of the reinforcing tapes also serving as a mounting for a plurality of U-shaped staples that form hinges by which multiple sheets are bound in an album.
The economical production of multiple pages of this type has proven to be a difficult task. An example of a machine for the production of multiple album pages is disclosed in U.S. Pat. No. 3,620,882 to Chou et al., which is assigned to the assignee of the present invention. In the Chou et al. machine, staples are supplied to a reinforcing tape for one side edge of successive album pages, adhesive on one surface of the tape is activated, individual sheets are manually fed into assembled relation with the tape, the assembled sheet and tape are pressed together, and successive assembled sheets and tape are advanced to a cut off station where the tape is severed. In order to apply reinforcing tape to the other side edge of the resulting page, it must be passed through the machine a second time for assembly with tape to which no staples have been applied.
Machines constructed in accordance with the Chou et al. patent have been used to produce satisfactory products, but such machines are relatively slow in operation, which correspondingly reduces the rate in which they produce album pages. They are also highly labor-intensive in that they require constant activity by operators to carry out the manual operations of individually loading, unloading and reloading each successive sheet.
In response to the problems of the prior art machines, attempts have been made to improve the efficiency in producing quality album pages. An example of such a machine is disclosed in U.S. Pat. No. 4,986,864 to Heim et al., which is assigned to the assignee of the present invention and incorporated herein by reference. In the Heim et al. machine, a pair of tapes are folded and pressed into overlapping adhered relation with the side edges of a base sheet to form a web consisting of a series of pages held together by intermediate pieces of the pair of tapes. The tapes, successive sheets and resulting web are drawn through the machine by a reciprocating carriage. During forward feeding movement of the carriage, the web is clamped to the carriage thereby conveying successive pages downstream through a page assembly station. The pair of tapes are clamped to a cut off station downstream from the page assembling station wherein the pieces of tape connecting the leading page to the remainder of the web are cut out to leave the leading page free for further processing.
While the Heim et al. machine has dramatically improved the speed at which album pages are produced, the drive system of this machine comprises a complicated arrangement of rods connected to a rocker arm for converting oscillating movement of the rocker arm into linear reciprocating movement of a carriage. While this mechanism is a dramatic improvement over the earlier page binding machines, its complicated arrangement limits its operating speed and requires substantial routine maintenance. Additionally, this prior art drive system often causes successive sheets to be out of register, i.e. having varying spacing therebetween, due to its complex mechanical arrangement.
Accordingly there is a need for an improvement to the prior art page binding method and machine for efficiently producing album pages of consistent high quality. Furthermore there is a need for such a machine having a simplified design thereby resulting in reduced construction costs and routine maintenance expenses.